Random Access Power Control Method and Apparatus and Communication System

ABSTRACT

A random access power control apparatus and method and a communication system. The random access power control apparatus includes: a first calculating unit configured to, by using a pathloss estimated based on an synchronization signal/physical broadcast channel block and/or a channel state information reference signal (CSI-RS) currently selected by a UE, calculate transmission power used by the UE in transmitting random access preambles. Hence, the UE may be adapted to UE random access procedures in such complex scenarios as multiple beams.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of U.S. application Ser.No. 16/450,273, which was filed on Jun. 24, 2019, now pending, which isa continuation application of International ApplicationPCT/CN2017/097220 filed on Aug. 11, 2017, the entire contents of eachare incorporated herein by reference.

TECHNICAL FIELD

This disclosure relates to the field of communication technologies, andin particular to a random access power control method and apparatus anda communication system.

BACKGROUND

In a long term evolution (LTE) system, a user equipment (UE) performs anindividual random access procedure attempt at a time, an initiatesanother random access procedure to again attempt to access when it isdetermined that this random access procedure attempt fails.

In a contention-based random access procedure, the UE randomly selects apreamble to transmit on a physical random access channel (PRACH). Innon-contention-based random access procedure, a base station indicatesthe UE to use a preamble, and indicates the UE to use a specific PRACHtime-frequency resource or indicates the UE to autonomously select atime-frequency resource.

It should be noted that the above description of the background ismerely provided for clear and complete explanation of this disclosureand for easy understanding by those skilled in the art. It should not beunderstood that the above technical solution is known to those skilledin the art as it is described in the background of this disclosure.

SUMMARY

In the LTE, transmission power of a preamble may be calculated by usingformula (1) below:

P _(PRACH)=min{P _(CMAX,c)(i),PREAMBLE_RECEIVED_TARGET_POWER+PL_(c)}[dBm]   (1);

where, P_(CMAX,c)(i) is maximum transmission power of a UE to a subframei in a cell c;

PL_(c) is a downlink pathloss of the cell c estimated by the UE;

PREAMBLE_RECEIVED_TARGET_POWER is preamble receiving target power, whichis expressed by formula (2) below:

PREAMBLE_RECEIVED_TARGET_POWER=preamblelnitialReceivedTargetPower+DELTA_PREAMBLE+(PREAMBLE_TRANSMISSION_COUNTER−1)*powerRampingStep   (2);

where, DELTA_PREAMBLE is a predefined power offset based on a preambleformat, preambleInitialReceivedTargetPower and powerRampingStep areinitial target receiving power and a power ramping step for the preambleconfigured by the cell, respectively, and PREAMBLE_TRANSMISSION_COUNTERis a preamble transmission counter value, an initial value of whichbeing 1; if one time of random access attempt fails, 1 is added to thecounter value in each time of restarting a time of random access attemptby the UE, and when a value to which 1 is added is greater than amaximum number of times of transmission configured by the cell, the UEreports a random access issue to a higher layer, and then the UE mayperform cell reselection.

In the LTE, communication scenarios of random access are relativelysimple, and in determining transmission power of a preamble, the numberof considered factors is relatively few.

However, it was found by the inventors that in future wirelesscommunication systems, such as a 5G system, and a new radio (NR) system,communication scenarios of random access become more complex, anduncertain factors possibly resulting in a failure of a random accessprocedure of a UE will be introduced. If an existing mechanism is stillused to determine transmission power of a preamble, requirements ofcomplex communication scenarios are hard to be satisfied. For example,in a scenario where a base station transmits multiple synchronizationsignals/physical broadcast channel blocks (SS/PBCH blocks), there existsa difference between pathlosses resulted from different SS/PBCH blocks.As the above difference is not taken into account in existing methodsfor determining transmission power of a preamble, it is hard toaccurately estimate the transmission power of the preamble in multi-beamscenarios. And there currently exists no method for solving the aboveproblem.

Hence, in consideration of complex communication scenario requirementsof future wireless communication, embodiments of this disclosure providea random access power control method and apparatus and a communicationsystem, which are adapted to complex scenarios of random access of a UE.

According to a first aspect of the embodiments of this disclosure, thereis provided a random access power control apparatus, including:

a first calculating unit configured to, by using a pathloss estimatedbased on an synchronization signal/physical broadcast channel block(SS/PBCH block) and/or a channel state information reference signal(CSI-RS) currently selected by UE, calculate transmission power used bythe UE in transmitting random access preambles.

According to a second aspect of the embodiments of this disclosure,there is provided a random access power control method, including:

calculating transmission power used by UE in transmitting random accesspreambles by using a pathloss estimated based on an synchronizationsignal/physical broadcast channel block (SS/PBCH block) and/or a channelstate information reference signal (CSI-RS) currently selected by theUE.

According to a third aspect of the embodiments of this disclosure, thereis provided a random access power control apparatus, including:

a second calculating unit configured to calculate transmission power ofa preamble by using a first parameter; wherein, the first parameterincludes the number of sequences (N_seq.beam) received by an individualreceiving beam of the UE, and/or a configuration parameter or subcarrierspacing adopted by the preamble, and/or a type of the UE, and/or gainsof transmission/receiving beams of the UE.

According to a fourth aspect of the embodiments of this disclosure,there is provided a random access power control method, including:

calculating transmission power of a preamble by using a first parameter;wherein, the first parameter includes the number of sequences(N_seq.beam) received by an individual receiving beam of the UE, and/ora configuration parameter or subcarrier spacing adopted by the preamble,and/or a type of the UE, and/or gains of transmission/receiving beams ofthe UE.

According to a fifth aspect of the embodiments of this disclosure, thereis provided a communication system, including a UE; the UE, by using apathloss estimated based on an synchronization signal/physical broadcastchannel block (SS/PBCH block) and/or a channel state informationreference signal currently selected by the UE, calculates transmissionpower used by the UE in transmitting random access preambles, or the UEcalculates transmission power of a preamble by using a first parameter.

An advantage of the embodiments of this disclosure exists in that incalculating the transmission power used by the UE in transmitting randomaccess preambles, influences of multiple parameters are taken intoaccount, which may be adapted for random access procedures of the UE incomplex scenarios.

With reference to the following description and drawings, the particularembodiments of this disclosure are disclosed in detail, and theprinciple of this disclosure and the manners of use are indicated. Itshould be understood that the scope of the embodiments of thisdisclosure is not limited thereto. The embodiments of this disclosurecontain many alternations, modifications and equivalents within thescope of the terms of the appended claims.

Features that are described and/or illustrated with respect to oneembodiment may be used in the same way or in a similar way in one ormore other embodiments and/or in combination with or instead of thefeatures of the other embodiments.

It should be emphasized that the term “comprise/include” when used inthis specification is taken to specify the presence of stated features,integers, blocks or components but does not preclude the presence oraddition of one or more other features, integers, blocks, components orgroups thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

Elements and features depicted in one drawing or embodiment of thedisclosure may be combined with elements and features depicted in one ormore additional drawings or embodiments. Moreover, in the drawings, likereference numerals assign corresponding parts throughout the severalviews and may be used to assign like or similar parts in more than oneembodiment.

The drawings are included to provide further understanding of thepresent disclosure, which constitute a part of the specification andillustrate the preferred embodiments of the present disclosure, and areused for setting forth the principles of the present disclosure togetherwith the description. It is obvious that the accompanying drawings inthe following description are some embodiments of this disclosure, andfor those of ordinary skills in the art, other accompanying drawings maybe obtained according to these accompanying drawings without making aninventive effort. In the drawings:

FIG. 1 is a flowchart of the random access power control method ofEmbodiment 1 of this disclosure;

FIG. 2 is a schematic diagram of performing random access attempt by theUE in Embodiment 1 of this disclosure;

FIG. 3 is a flowchart of the random access power control method ofEmbodiment 2 of this disclosure;

FIG. 4 is a schematic diagram of the random access power controlapparatus of Embodiment 3 of this disclosure;

FIG. 5 is a schematic diagram of the random access power controlapparatus of Embodiment 4 of this disclosure;

FIG. 6 is a schematic diagram of the UE of Embodiment 5 of thisdisclosure;

FIG. 7A is a schematic diagram of the communication system of Embodiment6 of this disclosure;

FIG. 7B is another schematic diagram of the communication system ofEmbodiment 6 of this disclosure;

FIG. 8 is a flowchart of the information indication method of Embodiment7 of this disclosure;

FIG. 9 is a flowchart of the information indication method of Embodiment8 of this disclosure;

FIG. 10 is a schematic diagram of the information indication apparatusof Embodiment 9 of this disclosure;

FIG. 11 is a schematic diagram of the information indication apparatusof Embodiment 10 of this disclosure;

FIG. 12 is a schematic diagram of the communication system of Embodiment11 of this disclosure;

FIG. 13 is a schematic diagram of the base station of Embodiment 11 ofthis disclosure; and

FIG. 14 is a schematic diagram of the UE of Embodiment 11 of thisdisclosure.

DETAILED DESCRIPTION

These and further aspects and features of the present disclosure will beapparent with reference to the following description and attacheddrawings. In the description and drawings, particular embodiments of thedisclosure have been disclosed in detail as being indicative of some ofthe ways in which the principles of the disclosure may be employed, butit is understood that the disclosure is not limited correspondingly inscope. Rather, the disclosure includes all changes, modifications andequivalents coming within the terms of the appended claims. Variousimplementations of the embodiments of this disclosure shall be describedwith reference to the accompanying drawings. These implementations areillustrative only, and are not intended to limit this disclosure.

In the embodiments of this disclosure, terms “first”, and “second”,etc., are used to differentiate different elements with respect tonames, and do not indicate spatial arrangement or temporal orders ofthese elements, and these elements should not be limited by these terms.Terms “and/or” include any one and all combinations of one or morerelevantly listed terms. Terms “contain”, “include” and “have” refer toexistence of stated features, elements, components, or assemblies, butdo not exclude existence or addition of one or more other features,elements, components, or assemblies.

In the embodiments of this disclosure, single forms “a”, and “the”,etc., include plural forms, and should be understood as “a kind of” or“a type of” in a broad sense, but should not defined as a meaning of“one”; and the term “the” should be understood as including both asingle form and a plural form, except specified otherwise. Furthermore,the term “according to” should be understood as “at least partiallyaccording to”, the term “based on” should be understood as “at leastpartially based on”, except specified otherwise.

In the embodiments of this disclosure, the term “communication network”or “wireless communication network” may refer to a network satisfyingany one of the following communication standards: long term evolution(LTE), long term evolution-advanced (LTE-A), wideband code divisionmultiple access (WCDMA), and high-speed packet access (HSPA), etc.

And communication between devices in a communication system may beperformed according to communication protocols at any stage, which may,for example, include but not limited to the following communicationprotocols: 1G (generation), 2G, 2.5G, 2.75G, 3G, 4G, 4.5G, and 5G andnew radio (NR) in the future, etc., and/or other communication protocolsthat are currently known or will be developed in the future.

In the embodiments of this disclosure, the term “network device”, forexample, refers to a device in a communication system that accesses aterminal device to the communication network and provides services forthe terminal device. The network device may include but not limited tothe following devices: a base station (BS), an access point (AP), atransmission reception point (TRP), a broadcast transmitter, a mobilemanagement entity (MME), a gateway, a server, a radio network controller(RNC), a base station controller (BSC), etc.

In the embodiments, the base station includes but not limited to a nodeB (NodeB or NB), an evolved node B (eNodeB or eNB), and a 5G basestation (gNB), etc. Furthermore, it may include a remote radio head(RRH), a remote radio unit (RRU), a relay, or a low-power node (such asa femto, and a pico, etc.). The term “base station” may include some orall of its functions, and each base station may provide communicationcoverage for a specific geographical area. And a term “cell” may referto a base station and/or its coverage area, which is dependent on acontext of the term.

In the embodiments of this disclosure, the term “user equipment (UE)” or“terminal equipment (TE)” refers to, for example, equipment accessing toa communication network and receiving network services via a networkdevice. The user equipment may be fixed or mobile, and may also bereferred to as a mobile station (MS), a terminal, a subscriber station(SS), an access terminal (AT), or a station, etc.

In the embodiments, the user equipment may include but not limited tothe following devices: a cellular phone, a personal digital assistant(PDA), a wireless modem, a wireless communication device, a hand-helddevice, a machine-type communication device, a lap-top, a cordlesstelephone, a smart cell phone, a smart watch, and a digital camera, etc.

For another example, in a scenario of the Internet of Things (IoT),etc., the user equipment may also be a machine or a device performingmonitoring or measurement. For example, it may include but not limitedto a machine-type communication (MTC) terminal, a vehicle mountedcommunication terminal, a device to device (D2D) terminal, and a machineto machine (M2M) terminal, etc.

In the embodiments of this disclosure, a random access procedure may bea contention-based random access procedure, or may be anon-contention-based random access procedure; according to whether anetwork device is able to uniquely identify a random access procedure ofa certain piece of UE, a random access procedure is divided into acontention-based random access procedure and a non-contention-basedrandom access procedure.

The embodiments of this disclosure shall be described below withreference to the accompanying drawings.

Embodiment 1

The embodiment provides a random access power control method, applicableto an apparatus side, such as a user equipment (UE) side, initiating arandom access procedure to a network side.

FIG. 1 is a flowchart of the random access power control method ofEmbodiment 1 of this disclosure. As shown in FIG. 1, the methodincludes:

block 101: transmission power used by UE in transmitting random accesspreambles is calculated by using a pathloss estimated based on ansynchronization signal/physical broadcast channel block (SS/PBCH block)and/or a channel state information reference signal (CSI-RS) currentlyselected by the UE.

According to the embodiment, the pathloss estimated based on thesynchronization signal/physical broadcast channel block (SS/PBCH block)and/or the channel state information reference signal (CSI-RS) selectedby the UE is taken into account in calculating the transmission power ofthe preambles, hence, it is adapted to UE random access procedures insuch complex scenarios as multiple beams.

In the embodiment, a base station may periodically transmit multiplesynchronization signals/physical broadcast channel blocks (SS/PBCHblocks), which may also be referred to as synchronization signal blocks(SSBs), in a manner of beam sweeping. The base station may configure aphysical random access channel resource/preamble set (PRACHresource/preamble set), and divide it into multiple subsets, differentSS/PBCH blocks being associated with different PRACH resource/preamblesubsets. And the UE may select a cell and an SS/PBCH block in the cell,thereby determining a PRACH resource/preamble subset associated with theSS/PBCH block, select a PRACH resource and a preamble from the PRACHresource/preamble subset, and use the PRACH resource to transmit amessage containing the preamble.

In the embodiment, in a case where a random access attempt fails, the UEmay reselect an SS/PBCH block from the cell, so as to switch into a newPRACH resource/preamble subset for performing a random access attempt.

In an embodiment, as an SS/PBCH block selected by the UE may be changed,according to the pathloss estimated based on the SS/PBCH block selectedby the UE, transmission power of a preamble corresponding to the SS/PBCHblock may be accurately calculated, hence, it is adapted to UE randomaccess procedures in such complex scenarios as multiple beams.

In an embodiment, the transmission power of the preamble may becalculated according to formula (3) below:

P _(PRACH)=min{P _(CMAX,c) ,P _(PRACH,SSB)} [dBm]  (3);

where, P_(CMAX,c) is maximum transmission power of the UE in a cell c,and P_(PRACH,SSB) is transmission power needed in transmitting thepreamble calculated by the UE according to a power ramping counter andthe pathloss estimated based on the SS/PBCH block; for example,P_(PRACH,SSB) may be obtained according to formula (4) below:

P _(PRACH,SSB)=PREAMBLE_RECEIVED_TARGET_POWER+PL1  (4);

where, PL1 is the pathloss estimated based at least on the SS/PBCH blockselected by the UE, and PREAMBLE_RECEIVED_TARGET_POWER denotes preamblereceiving target power, which may be obtained based on the power rampingcounter; for example, PREAMBLE_RECEIVED_TARGET_POWER may be obtainedaccording to formula (5) below:

PREAMBLE_RECEIVED_TARGET_POWER=preambleInitialReceivedTargetPower+DELTA_PREAMBLE+(POWER_RAMPING_COUNTER−1)*powerRampingStep  (5);

-   -   where, preambleInitialReceivedTargetPower and powerRampingStep        are initial target receiving power and a power ramping step for        the preamble configured by the cell, respectively,        DELTA_PREAMBLE is a predefined power offset based on a preamble        format, and POWER_RAMPING_COUNTER denotes the power ramping        counter.

In an embodiment, an initial value of the power ramping counter may be1, and 1 may be added to the power ramping counter in each time ofrestarting random access attempt by the UE.

In an embodiment, each time of restarting a time of random accessattempt by the UE may make 1 to be added to a preamble transmittingcounter PREAMBLE_TRANSMISSION_COUNTER.

In an embodiment, the power ramping counter POWER_RAMPING_COUNTER may beequal to or unequal to the preamble transmitting counterPREAMBLE_TRANSMISSION_COUNTER.

In an embodiment, when a value to which 1 is added to the preambletransmitting counter is greater than a maximum number of times oftransmission configured by the cell, the UE may report a first randomaccess issue to a higher layer, and then the UE may perform cellreselection. In an embodiment, PL1 may be calculated based on particularimplementation of the UE. For example, corresponding PL1 may becalculated based on a measurement value of receiving power (RSRP1) ofthe UE to which an SS/PBCH block currently selected by the UEcorresponds. For example, the calculation may be performed according toformula (4-1) below:

PL1=transmission power of the base station—receiving power (RSRP1) ofthe UE   (4-1).

In an embodiment, another possible case of the random access procedureof the UE is that for the UE in a CONNECTED mode, the UE may beconfigured with channel state information reference signals (CSI-RSs)used for measurement, and different CSI-RSs may corresponding todifferent beams, so as to be associated with different physical randomaccess channel (PRACH) resource/preamble sets, and the UE may, accordingto a measurement result based on the CSI-RSs, select PRACH resourcescorresponding to the CSI-RSs for performing random access.

In block 101 of an embodiment, the transmission power of the preamblemay also be calculated by using a pathloss estimated based the CSI-RSsconfigured for the UE. For example, P_(PRACH,SSB) may be calculatedaccording to formula (4-2) below:

P _(PRACH,SSB)=PREAMBLE_RECEIVED_TARGET_POWER+PL2  (4-2);

-   -   where, PL2 is the pathloss estimated based on the CSI-RSs        configured for the UE.

In block 101 of an embodiment, in calculating the transmission power ofthe preamble, either one of PL1 and PL2 may be used, or PL1 and PL2 areused to form PL3, and PL1 in formula (4) is replaced with PL3.

In an embodiment, as shown in FIG. 1, the method further includes:

block 102: a power ramping counter and/or a power ramping step are/isset in obtaining a reported random access issue related to reselectingan synchronization signal/physical broadcast channel block by the UE.

In an embodiment, in obtaining the reported random access issue (i.e. asecond random access issue) related to reselecting an synchronizationsignal/physical broadcast channel block by the UE, the transmissionpower of the UE for transmitting the preamble may be controlled bysetting the power ramping counter and/or the power ramping step, therebyavoiding influence of over high power to other UE in transmitting thepreamble to which the reselected synchronization signal/physicalbroadcast channel block corresponds.

In an embodiment, the power ramping counter and/or the power rampingstep may be set by a higher layer of the UE. For example, the powerramping counter and/or the power ramping step may be reset to be of apredetermined value; for example, the power ramping counter is set to be0 or to be halved.

In an embodiment, in a case where the power ramping counter and/or thepower ramping step are(is) set in block 102, the UE may calculate thetransmission power of the preamble according to the newly-set powerramping counter and/or power ramping step in a subsequent random accessattempt, hence, the transmission power of the preamble may becontrolled.

In an embodiment, as shown in FIG. 1, the method further includes:

block 103: the random access issue related to reselecting ansynchronization signal/physical broadcast channel block by the UE isreported when the UE reselects an synchronization signal/physicalbroadcast channel block (SS/PBCH block).

In an embodiment, as shown in FIG. 1, the method further includes:

block 104: the random access issue related to reselecting ansynchronization signal/physical broadcast channel block by the UE isreported when the UE reselects an synchronization signal/physicalbroadcast channel block (SS/PBCH block) and a first predeterminedcondition is satisfied.

In an embodiment, the first predetermined condition concerned in block104 may be at least one of the following conditions: the power rampingcounter is greater than a first threshold (N_thre); and transmissionpower calculated by the UE by using a pathloss estimated based on thesynchronization signal/physical broadcast channel block (SS/PBCH block)reselected by the UE is greater than a second threshold (P_thre).

In blocks 103 and 104 of an embodiment, the random access issue (i.e.the second random access issue) related to reselecting ansynchronization signal/physical broadcast channel block by the UE may bereported to the higher layer of the UE, and after receiving the secondrandom access issue, the higher layer of the UE sets the power rampingcounter and/or the power ramping step.

In an embodiment, as shown in FIG. 1, the method further includes:

block 102 a: the power ramping counter and/or the power ramping stepare/is set when the UE reselects an synchronization signal/physicalbroadcast channel block, or when the UE reselects an synchronizationsignal/physical broadcast channel block and a second predeterminedcondition is satisfied.

In block 102 a of an embodiment, the power ramping counter and/or thepower ramping step may be set without needing to report the secondrandom access issue. For example, when the unit for setting the powerramping counter and/or the power ramping step and the unit for countingare located at the same layer of the UE, the power ramping counterand/or the power ramping step may be set without needing to report thesecond random access issue.

In an embodiment, the second predetermined condition may be at least oneof conditions listed in the first predetermined condition.

In an embodiment, as shown in FIG. 1, the method further includes:

block 105: selecting a target synchronization signal/physical broadcastchannel block is determined when parameters related to ansynchronization signal/physical broadcast channel block (SS/PBCH block)currently selected by the UE satisfy a third predetermined condition,and/or parameters related to the target synchronization signal/physicalbroadcast channel block (SS/PBCH block) satisfy a fourth predeterminedcondition.

Hence, when the UE determines to restart a random access attempt, it maydetermine whether to reselect an synchronization signal/physicalbroadcast channel block (SS/PBCH block), which may avoid selectingSS/PBCH blocks too frequently, and avoid ping-ponging effects betweenthe SS/PBCH blocks.

In an embodiment, the third predetermined condition may be any one ofthe following conditions or a combination thereof:

(1) receiving power of the currently selected synchronizationsignal/physical broadcast channel block is less than a third threshold;for example, the UE may compare the receiving power RSRP of thecurrently selected SS/PBCH block with a third threshold X [dBm], and mayreselect an SS/PBCH block if RSRP<X [dBm], otherwise, the UE may notreselect a new SS/PBCH block;

(2) a difference between transmission power P_(PRACH,SSB) of a preamblecalculated based on the currently selected synchronizationsignal/physical broadcast channel block and maximum transmission powerP_(CMAX,c) of the UE in a cell is greater than a fourth threshold Z[dB];

for example, when (P_(PRACH,SSB)−P_(CMAX,C))>Z [dB], the UE may reselectan SS/PBCH block, otherwise, the UE does not reselect a new SS/PBCHblock;

(3) the number of times of transmitting at the maximum transmissionpower of the preamble calculated based on the currently selectedsynchronization signal/physical broadcast channel block is greater thanor equal to a fifth threshold N;

for example, the maximum transmission power of the preamble calculatedbased on the currently selected SS/PBCH block is Pmax, and when thenumber of times of transmitting the preamble by the UE by using themaximum transmission power Pmax is greater than or each to N, the UE mayreselect an SS/PBCH block in retransmitting a preamble next time,otherwise, the UE does not reselect a new SS/PBCH block;

(4) a time of attempting random access based on the currently selectedsynchronization signal/physical broadcast channel block is greater thanor equal to a sixth threshold T [ms];

for example, if the time of attempting random access by the UE based onthe currently selected SS/PBCH block is greater than or equal to thesixth threshold T [ms], it may reselect an SS/PBCH block, otherwise, theUE does not reselect a SS/PBCH block.

In an embodiment, the fourth predetermined condition may include atleast one of the following conditions:

(1) a difference between receiving power of the target synchronizationsignal/physical broadcast channel block and the receiving power of thecurrently selected synchronization signal/physical broadcast channelblock is greater than or equal to a seventh threshold;

for example, the UE may compare the difference between receiving powerRSRP2 of the target SS/PBCH block and the receiving power RSRP1 of thecurrently selected SS/PBCH block (RSRP2−RSRP1) with the sevenththreshold Y [dB], and select the target SS/PBCH block as a new SS/PBCHblock if (RSRP2−RSRP1)≥Y [dB], otherwise, the UE does not reselect a newSS/PBCH block;

(2) a difference between the maximum transmission power P_(CMAX,c) ofthe UE in a cell and transmission power P_(_SSB) of the preamblecalculated based on the target synchronization signal/physical broadcastchannel block is greater than an eighth threshold W[dB];

for example, when P_(CMAX,c)−P_(_SSB)−>W dB, the UE may select thetarget SS/PBCH block as a new SS/PBCH block, otherwise, the UE does notreselect a new SS/PBCH block. In an embodiment, the first threshold,and/or the second threshold, and/or the third threshold, and/or thefourth threshold, and/or the fifth threshold, and/or the sixththreshold, and/or the seventh threshold, and/or the eighth threshold,may be configured by the base station for the UE. For example, the basestation may configure via a system message, and/or RRC signaling, and/orphysical layer control signaling. And furthermore, an embodiment is notlimited thereto; for example, the UE may also configure any one or twoor more of the first threshold to the eighth threshold.

A method for performing random access attempt by the UE of an embodimentshall be described below with reference to an example. FIG. 2 is aflowchart of the method for performing random access attempt by the UEof an embodiment. As shown in FIG. 2, the method includes:

block 201: the UE determines to restart a random access attempt when aprevious time of random access attempt fails;

block 202: the UE calculates the transmission power P_(PRACH,SSB) of thepreamble according to the power ramping counter PRC and the pathlossestimated based on the currently selected SS/PBCH block;

block 203: it is determined whether P_(PRACH,SSB)−P_(CMAX,c) is greaterthan the threshold Z[dB], entering into block 204 when it is no, andentering into block 207 when it is yes;

block 204: an SS/PBCH block is not reselected;

block 205: 1 is added to the power ramping counter PRC to update thePRC;

block 206: the UE recalculates the transmission power P_(PRACH),SSB ofthe preamble according to the updated power ramping counter PRC and thepathloss estimated based on the currently selected SS/PBCH block;

block 207: the UE reselects an SS/PBCH block, and selects a PRACHresource corresponding to the reselected SS/PBCH block;

block 208: it is determined whether the power ramping counter PRC isgreater than the first threshold N_thre, entering into block 210 when itis no, and entering into block 209 when it is yes;

block 209: the second random access issue is reported to the higherlayer, and the higher layer resets the power ramping counter PRC, suchas setting the power ramping counter PRC to be half of the originalvalue, or resetting the power ramping step by the higher layer, such assetting the power ramping step to be half of the original value;

block 210: the UE recalculates the transmission power P_(PRACH),SSB ofthe preamble according to the power ramping counter PRC, the powerramping step and the pathloss estimated based on the currently selectedSS/PBCH block; and block 211: the UE determines the transmission powerP_(PRACH) of the preamble according to P_(PRACH),SSB and based on theabove formula (3), and transmitting the preamble.

In FIG. 2, a block shown by a dotted-line frame 20 denotes a processingof reporting the second random access issue to the higher layer by theUE after selecting a new SS/PBCH block.

According to the embodiment, the pathloss estimated based on thesynchronization signal/physical broadcast channel block (SS/PBCH block)selected by the UE is taken into account in calculating the transmissionpower of the preamble, which is adapted for random access procedures ofthe UE in such complex scenarios as multiple beams. In the case wherethe UE selects a new SS/PBCH block, the power ramping counter PRC andthe power ramping step are set, thereby controlling the transmissionpower of the preamble, and avoiding influence to other UE. And the UEwill select a new SS/PBCH block to transmit the preamble only when thepredetermined condition is satisfied, thereby avoiding ping-pongingeffects between the SS/PBCH blocks.

Embodiment 2

The embodiment provides a random access power control method, applicableto an apparatus side, such as a user equipment (UE) side, initiating arandom access procedure to a network side.

FIG. 3 is a flowchart of the random access power control method ofEmbodiment 2 of this disclosure. As shown in FIG. 3, the methodincludes:

block 301: transmission power of a preamble is calculated by using afirst parameter. In an embodiment, the first parameter may include, forexample, the number of sequences (N_seq.beam) received by an individualreceiving beam of the UE, and/or a configuration parameter or subcarrierspacing (numerology/SCS) adopted by the preamble, and/or a type of theUE, and/or gains of transmission/receiving beams (TX/RX beams) of theUE.

Furthermore, in an embodiment, the first parameter may not be limited tothe above listed parameters.

According to an embodiment, the first parameter is taken into account incalculating the transmission power of the preamble, such that thetransmission power of the preamble is able to satisfy requirements ofcomplex communication scenarios.

In an embodiment, the transmission power P′_(PRACH) of the preamble maybe determined according to formula (6) below:

P _(PRACH)=min{P _(CMAX,c) ,P′ _(PRACH,SSB)} [dBm]  (6);

where, P_(CMAX,c) is maximum transmission power of the UE in a cell c,and P_(RACH,SSB) is transmission power needed in transmitting thepreamble calculated by the UE according to a power ramping counter andan estimated value of a pathloss; for example, the first parameter maybe used for determining a power offset, and the power offset may bebrought into the formula for calculating P′_(PRACH).

In one implementation, P′^(PRACH) may be calculated according to thepower offset DELTA_P set by the first parameter, the estimated value ofthe pathloss and a preamble receiving target power(PREAMBLE_RECEIVED_TARGET_POWER) obtained based on the power rampingcounter. For example, P′_(PRACH) may be obtained according to formula(7) below:

P′ _(PRACH,SSB)=PREAMBLE_RECEIVED_TARGET_POWER+PL′+DELTA_P  (7);

where, PL′ is the estimated value of the pathloss of the pathtransmitting the preamble, which may be a downlink pathloss of the cellc estimated by the UE. Hence, PL′ may be equal to PLc in formula (1).Furthermore, the estimated value of the pathloss may also be a pathlossestimated based on the SS/PBCH block selected by the UE. Hence, PL′ maybe equal to PL1 in formula (4), or PL2 or PL3 in formula (4-2), and in acase where PL′ may be equal to PL1, or PL2, or PL3 in formula (4), therandom access method of an embodiment may be merged with the randomaccess method of Embodiment 1, that is, block 301 in FIG. 3 may becombined with block 101 in FIG. 1. Hence, the transmission power of thepreamble is calculated according to the power ramping counterPOWER_RAMPING_COUNTER, the pathloss estimated based on thesynchronization signal/physical broadcast channel block (SS/PBCH block)selected by the UE and/or a channel state information reference signal(CSI-RS) and the first parameter; and PREAMBLE_RECEIVED_TARGET_POWERdenotes the preamble receiving target power, and may be obtained basedon the power ramping counter. For example,PREAMBLE_RECEIVED_TARGET_POWER may be obtained according to formula (5)above.

In another implementation, P′PRACH,SSB may be calculated according tothe preamble receiving target power obtained based on the power offsetDELTA_P set by the first parameter and the power ramping counter and thepathloss PL′. For example, P′_(PRACH,SSB) may be obtained according toformula (8) below:

P _(PRACH,SSB)=PREAMBLE_RECEIVED_TARGET_POWER′+PL′  (8);

where, PREAMBLE_RECEIVED_TARGET_POWER′ is the preamble receiving targetpower obtained based on the power offset DELTA_P set by the firstparameter and the power ramping counter; for example,PREAMBLE_RECEIVED_TARGET_POWER′ may be obtained by using formula (9)below:

PREAMBLE_RECEIVED_TARGET_POWER′=preambleInitialReceivedTargetPower+DELTA_PREAMBLE+DELTA_P+(POWER_RAMPING_COUNTER−1)*powerRampingStep  (9);

where, preambleInitialReceivedTargetPower and powerRampingStep areinitial target receiving power and a power ramping step for the preambleconfigured by the cell, respectively, DELTA_PREAMBLE is a predefinedpower offset based on a preamble format, POWER_RAMPING_COUNTER denotesthe power ramping counter, and DELTA_P is the power offset according toa feature parameter.

In the above formulae (7) and (9), the power offset DELTA_P isintroduced into the calculation of P′PRACH,SSB in a form of additionoperation. However, the embodiment is not limited thereto, and the poweroffset DELTA_P may also be introduced into the calculation ofP′PRACH,SSB in a form of subtraction operation, and/or multiplicationoperation, and/or division operation, and/or exponential operation,and/or logarithmic operation, etc. Furthermore, the power offset DELTA_Pmay also be introduced into formulae (7) and (9) under somepredetermined conditions, so as to calculate P′PRACH,SSB. For example,in a case where the preamble is a short sequence, for formula (9),DELTA_P may be reserved and DELTA_PREAMBLE may be deleted, that is,DELTA_PREAMBLE is replaced with DELTA_P. Moreover, in a case where thepreamble is a long sequence, for formula (9), DELTA_PREAMBLE may bereserved and DELTA_P may be deleted.

A method of determination of DELTA_PREAMBLE in formulae (5) and (9)shall be described below.

DELTA_PREAMBLE may be determined according to the preamble format.

In an embodiment, for a preamble of a long sequence (a sequence length Lis 839), values of DELTA_PREAMBLE to which other formats correspond maybe determined by taking format 0 (839) as a reference format; for apreamble of a short sequence (a sequence length L is 127/139, i.e. 127or 139), values of DELTA_PREAMBLE to which other formats correspond maybe determined by taking a format (such as format A0) in the shortsequence (127/139) as a reference format; and a value of DELTA_PREAMBLEto which the reference format of the short sequence corresponds may beobtained by taking a value of DELTA_PREAMBLE to which the referenceformat of the long sequence corresponds as a reference. Table 1 showsvalues of DELTA_PREAMBLE to which the formats correspond.

TABLE 1 Preamble Format DELTA_PREAMBLE 0  0 dB 1 −3 dB 2 −6 dB 3  6 dBShort sequence formats 14 dB (assuming that a reference format is A0,and Δf = 15 kHz)

In Table 1, for formats 0, 1, 2, 3 to which the long sequencecorresponds, corresponding DELTA_PREAMBLE may be determined directlyfrom Table 1; wherein, values of DELTA_PREAMBLE to which formats 1, 2, 3corresponds are obtained by taking a value of DELTA_PREAMBLE to whichformat 0 corresponds as a reference. For the formats to which the shortsequence corresponds, values of DELTA_PREAMBLE to which the shortsequence reference formats correspond may be taken as the values ofDELTA_PREAMBLE to which the formats correspond. And the values ofDELTA_PREAMBLE to which the short sequence reference formats correspondare, for example, 14 dB, and such a numeral value may be a valueobtained by taking a value of 0 of DELTA_PREAMBLE to which format 0corresponds as a reference.

Furthermore, in Table 1, Δf=15 kHz denotes a bandwidth of a subcarrieradopted by the preamble.

Moreover, Table 1 is illustrative only, and the values of DELTA_PREAMBLEto which the formats correspond may also be other values.

Method for calculating P′PRACH,SSB according to feature parameters shallbe described below.

1. Calculating P′PRACH,SSB according to the number of sequences(N_seq.beam) received by an individual receiving beam of the UE

The power offset determined according to N_seq.beam isDELTA_P=DELTA_NoS. In an embodiment, DELTA_NoS to which the formats ofthe preamble of a long sequence (a sequence length L is 839) correspondand the formats of the preamble of a short sequence (a sequence length Lis 127/139) correspond are different. Table 2 is a list of DELTA_NoS towhich the preamble of a long sequence corresponds.

TABLE 2 Format L DELTA_NoS 0 839 0 dB 1 839 0 dB 2 839 0 dB 3 839 0 dB

Table 3 is a list of DELTA_NoS to which the preamble of a short sequencecorresponds. For example, if format AO is taken as a reference format tocalculate DELTA_NoS to which the short sequence formats correspond,DELTA_NoS may be determined according to formula (10) below:

DELTA_NoS=

log(N_seq.beam)

  (10).

TABLE 3 L = 127/139 # of Format Sequence N_seq.beam DELTA_NoS A0 (shortsequence 1 1 0 dB reference format) A1 2 1 0 dB 2 −3 dB A2 4 1 0 dB 2 −3dB 4 −6 dB A3 6 1 0 dB 2 −3 dB 3 −4 dB 6 −7 dB B0 1 1 0 dB B1 2 1 0 dB 2−3 dB B2 4 1 0 dB 2 −3 dB 4 −6 dB B3 6 1 0 dB 2 −3 dB 3 −4 dB 6 −7 dB B412 1 0 dB 2 −3 dB 3 −4 dB 4 −6 dB 6 −7 dB 12 −10 dB C0 1 1 0 dB C1 2 1 0dB 2 −3 dB

In Table 1 and Table 2, the format refers to a preamble format, “# ofsequence” denotes an index of a received sequence.

For a long sequence preamble or a short sequence preamble, according toits N_seq.beam, DELTA_NoS shown in Table 2 or Table 3 may be substitutedinto formula (7), or (8) or (9), so as to obtain P′PRACH,SSB throughcalculation.

Furthermore, in an embodiment, DELTA_NoS may be introduced into formula(7) or (9) under some predetermined conditions, so as to obtainP′PRACH,SSB through calculation. For example, in a case where thepreamble is a short sequence (127/139), DELTA_NoS may be reserved andDELTA_PREAMBLE may be deleted in formula (7) or (9), that is, an effectof DELTA_PREAMBLE on the transmission power of the preamble is takeninto account only when the preamble is a short sequence (127/139), andDELTA_PREAMBLE is replaced with DELTA_NoS. Furthermore, in a case wherethe preamble is a long sequence (839), DELTA_PREAMBLE may be reservedand DELTA_NoS may be deleted in formula (7) or (9); for example, formula(9) may be written into the following form (9a):

PREAMBLE_RECEIVED_TARGET_POWER′=preambleInitialReceivedTargetPower+DELTA_PREAMBLE(for 839)/DELTA_NoS (for127/139)+(POWER_RAMPING_COUNTER−1)*powerRampingStep  (9a);

where, DELTA_PREAMBLE(for 839)/DELTA_NoS(for 127/139) denotes that inthe case where the preamble is a short sequence (127/139), values ofDELTA_NoS are taken, for example, the values of DELTA_NoS may bedetermined with reference Table 3 above, and in the case where thepreamble is a long sequence (839), values of DELTA_PREAMBLE are taken,for example, the values of DELTA_PREAMBLE may be determined withreference Table 1 above.

2. Calculating P′PRACH,SSB according to the configuration parameter orsubcarrier spacing (numerology/SCS) adopted by the preamble

In an embodiment, for the case of short sequence preamble, thetransmission power of the preamble may be calculated based on theconfiguration parameter or subcarrier spacing adopted by the preamble.

The power offset determined based on the configuration parameter orsubcarrier spacing (numerology/SCS) adopted by the preamble may beexpressed as DELTA_P=DELTA_SCS; for example, DELTA_SCS may be determinedaccording to (11) below:

DELTA SCS=10 log(μ+1)  (11);

where, μ denotes the configuration parameter of the subcarrier spacingadopted by the preamble, and the subcarrier spacing Δf adopted by thepreamble may be expressed as Δf=15.2^(μ) kHz, a value of μ being, forexample, 0, or 1, or 2, or 3, etc.

For example, transmission power needed by a preamble with an SCS being15 kHz is taken as reference transmission power, and Δf=15.2^(μ) kHzdenotes the subcarrier spacing adopted by the preamble. Taking format A2as an example, the power offset DELTA_SCS relative to the referencetransmission power may be as shown in Table 4 below.

TABLE 4 # of SCS/μ ∈ {0, 1, 2, 3} Format Sequence (Δf = 15 · 2^(μ) kHz)DELTA_SCS A2 4 15 kHz/0 0 30 kHz/1 3 dB 60 kHz/2 6 dB 120 kHz/3  9 dB

3. Calculating P′_(PRACH,SSB) according to the type of the UE

In an embodiment, the type of the UE may refer to, for example, a typeof service of the UE, and the power offset determined based on the typeof the UE may be denoted as DELTA_P=DELTA_UE.

In an embodiment, a list of correspondence between a type of the UE andvalues of DELTA_P=DELTA_UE, hence, a value of DELTA_P=DELTA_UE to whicha type of the UE corresponds may be determined.

Table 5 below shows an example of correspondence between a type of theUE and values of DELTA_P=DELTA_UE.

TABLE 5 Value of Type of UE DELTA_UE 0 (with beam 0 dB correspondence) 1(without beam 3 dB correspondence)

In the above table, a type 0 of the UE denotes that a type of the UE isable to perform beam correspondence, and a value of DELTA_P=DELTA_UE towhich the type corresponds is 0 dB, and a type 1 of the UE denotes thata type of the UE is unable to perform beam correspondence, and a valueof DELTA_P=DELTA_UE to which the type corresponds is 3 dB.

4. Calculating P′_(PRACH,SSB) according to gains oftransmission/receiving beams of the UE

In an embodiment, the power offset determined according to the gains oftransmission/receiving beams of the UE may be expressed asDELTA_P=DELTA_Beam.

In an embodiment, values of DELTA_P=DELTA_Beam to which the gains oftransmission/receiving beams of the UE correspond may be determined by apredetermined list of correspondence between gains oftransmission/receiving beams of the UE and values of DELTA_P=DELTA_Beamor a formula.

In an embodiment, P′_(PRACH,SSB) may be calculated by taking at leastone of DELTA_NoS, DELTA_SCS, DELTA_UE and DELTA_Beam, or a combinationof two or more thereof, as DELTA_P.

In an embodiment, the UE may, in a manner identical to that inEmbodiment 1, determine whether to reselect an SS/PBCH block to transmitthe preamble, and in a case where the UE reselects an SS/PBCH block, theUE may, in the manner of Embodiment 1, determine an occasion ofreporting the second random access issue by the UE, and manners of thehigher layer of the UE for resetting a power ramping counter and/or apower ramping step are identical to those in Embodiment 1.

5. Calculating P′_(PRACH,SSB) according to the number of sequences andthe number of receiving beams contained in the preamble

Particulars are similar to those in 1.

According to an embodiment, in calculating the transmission power of thepreamble, the first parameter is taken into account, hence, thetransmission power of the preamble is enabled to satisfy requirements ofcomplex communication scenarios.

Embodiment 3

Embodiment 3 provides a random access power control apparatus. As aprinciple of the apparatus for solving problems is similar to those ofthe methods in embodiments 1 and 2, the implementations of the methodsin embodiments 1 and 2 may be referred to for implementation of theapparatus, with identical contents being not going be described hereinany further.

FIG. 4 is a schematic diagram of the random access power controlapparatus. As shown in FIG. 4, a random access power control apparatus400 includes a first calculating unit 401 configured to calculatetransmission power used by the UE in transmitting random accesspreambles.

In an embodiment, by using a pathloss estimated based on ansynchronization signal/physical broadcast channel block (SS/PBCH block)and/or a channel state information reference signal currently selectedby UE, the first calculating unit 401 calculates the transmission powerused by the UE in transmitting random access preambles.

In an embodiment, as shown in FIG. 4, the apparatus 400 may furtherinclude a first setting unit 402 configured to set a power rampingcounter and/or a power ramping step in obtaining a reported randomaccess issue related to reselecting an synchronization signal/physicalbroadcast channel block by the UE.

In an embodiment, the first setting unit 402 may be achieved by a higherlayer of the UE, the higher layer of the UE being, for example, a mediaaccess control (MAC) layer.

In an embodiment, as shown in FIG. 4, the apparatus 400 may furtherinclude a first reporting unit 403 configured to report the randomaccess issue related to reselecting an synchronization signal/physicalbroadcast channel block by the UE to the setting unit 402 when the UEreselects an synchronization signal/physical broadcast channel block(SS/PBCH block).

In an embodiment, as shown in FIG. 4, the apparatus 400 may furtherinclude a second reporting unit 404 configured to report the randomaccess issue related to reselecting an synchronization signal/physicalbroadcast channel block by the UE to the setting unit 402 when the UEreselects an synchronization signal/physical broadcast channel block anda first predetermined condition is satisfied.

In an embodiment, the first predetermined condition is at least one ofthe following conditions:

the power ramping counter is greater than a first threshold; and

transmission power calculated by the UE by using a pathloss estimatedbased on the synchronization signal/physical broadcast channel blockreselected by the UE is greater than a second threshold.

In an embodiment, as shown in FIG. 4, the apparatus 400 may furtherinclude a second setting unit 402 a configured to set the power rampingcounter and/or the power ramping step when the UE reselects ansynchronization signal/physical broadcast channel block, or when the UEreselects an synchronization signal/physical broadcast channel block anda second predetermined condition is satisfied.

In an embodiment, the second setting unit 402 a may set the powerramping counter and/or the power ramping step without needing to reportthe random access issue related to reselecting an synchronizationsignal/physical broadcast channel block by the UE (i.e. the secondrandom access issue) to the second setting unit 402 a; wherein, thesecond setting unit 402 a, for example, may be located in a physicallayer of the UE.

In an embodiment, the second predetermined condition may be at least oneof conditions listed in the first predetermined condition.

In an embodiment, as shown in FIG. 4, the apparatus 400 may furtherinclude a first determining unit 405 configured to determine to select atarget synchronization signal/a physical broadcast channel block whenparameters related to an synchronization signal/physical broadcastchannel block (SS/PBCH block) currently selected by the UE satisfy athird predetermined condition, and/or parameters related to the targetsynchronization signal/physical broadcast channel block (SS/PBCH block)satisfy a fourth predetermined condition.

In an embodiment, the third predetermined condition includes at leastone of the following conditions:

receiving power of the currently selected synchronizationsignal/physical broadcast channel block is less than a third threshold;

a difference between transmission power of a preamble calculated basedon the currently selected synchronization signal/physical broadcastchannel block and maximum transmission power of the UE in a cell isgreater than a fourth threshold;

the number of times of transmitting at the maximum transmission power ofthe preamble calculated based on the currently selected synchronizationsignal/physical broadcast channel block is greater than or equal to afifth threshold; and a time of attempting random access based on thecurrently selected synchronization signal/physical broadcast channelblock is greater than or equal to a sixth threshold.

In an embodiment, the fourth predetermined condition includes at leastone of the following conditions:

a difference between receiving power of the target synchronizationsignal/physical broadcast channel block and the receiving power of thecurrently selected synchronization signal/physical broadcast channelblock is greater than or equal to a seventh threshold; and

a difference between the maximum transmission power of the UE in a celland transmission power of the preamble calculated based on the targetsynchronization signal/physical broadcast channel block is greater thanan eighth threshold.

In an embodiment, in calculating the transmission power, the firstcalculating unit 401 may calculate the transmission power according tofeature parameters related to the UE, that is, the first calculatingunit 401 may calculate the transmission power used by the UE intransmitting the preamble in the random access procedure according tothe power ramping counter, the pathloss estimated based on thesynchronization signal/physical broadcast channel block (SS/PBCH block)and/or the channel state information reference signal (CSI-RS) selectedby the UE and the feature parameters related to the UE.

For example, the first calculating unit 401 may calculate thetransmission power according to the power offset set by the firstparameter, the pathloss and the preamble receiving target power obtainedbased on the power ramping counter; or, the first calculating unit 401may calculate the transmission power according to the preamble receivingtarget power obtained based on the power offset set by the firstparameter and the power ramping counter and the pathloss.

In an embodiment, the first parameter may include: the number ofsequences (N_seq.beam) received by individual receiving beams of the UE,and/or the number of sequences and the number of receiving beamscontained in a preamble, and/or a configuration parameter or asubcarrier spacing employed by the preamble, and/or a type of the UE,and/or gains of transmission/receiving beams of the UE.

In an embodiment, an effect of the first parameter on the transmissionpower may be taken into account under a predetermined condition. Forexample, when the preamble is a short sequence (127/139), the effect ofthe first parameter on the transmission power is taken into account, andwhen the preamble is a long sequence (839), the effect of the firstparameter on the transmission power is not taken into account.

In an embodiment, reference may be made to description in Embodiment 2for calculating the power offset based on the first parameter andcalculating the transmission power, which shall not be described hereinany further.

According to the random access power control apparatus of theembodiment, random access procedures of the UE in such complex scenariosas multiple beams may be adapted for. In the case where the UE selects anew SS/PBCH block, the power ramping counter PRC and the power rampingstep are set, thereby controlling the transmission power of thepreamble, and avoiding influence to other UE. And the UE will select anew SS/PBCH block to transmit the preamble only when the predeterminedcondition is satisfied, thereby avoiding ping-ponging effects betweenthe SS/PBCH blocks.

Embodiment 4

Embodiment 4 provides a random access power control apparatus. As aprinciple of the apparatus for solving problems is similar to those ofthe methods in Embodiment 2, the implementations of the method inEmbodiment 2 may be referred to for implementation of the apparatus,with identical contents being not going be described herein any further.

FIG. 5 is a schematic diagram of the random access power controlapparatus. As shown in FIG. 5, a random access power control apparatus500 includes a second calculating unit 501 configured to calculatetransmission power used by UE in transmitting a preamble in a randomaccess procedure.

In an embodiment, the second calculating unit 501 may calculate thetransmission power according to a first parameter related to the UE;wherein, the first parameter includes the number of sequences(N_seq.beam) received by an individual receiving beam of the UE, and/ora configuration parameter or subcarrier spacing adopted by the preamble,and/or a type of the UE, and/or gains of transmission/receiving beams ofthe UE.

In an embodiment, reference may be made to description in Embodiment 2for calculating the power offset based on the first parameter andcalculating the transmission power, which shall not be described hereinany further.

According to the random access power control apparatus of thisembodiment, random access procedures of the UE in such complex scenariosas multiple beams may be adapted for.

Embodiment 5

Embodiment 5 provides UE, configured with the random access powercontrol apparatus 400 describe in Embodiment 3 or the random accesspower control apparatus 500 describe in Embodiment 4.

FIG. 6 is a schematic diagram of a structure of the UE of the embodimentof this disclosure. As shown in FIG. 6, UE 600 may include a centralprocessing unit 601 and a memory 602, the memory 602 being coupled tothe central processing unit 601. For example, the memory 602 may storevarious data, and furthermore, it may store a program for informationprocessing, and execute the program under control of the centralprocessing unit 601, so as to perform random access.

In one implementation, the functions of the random access power controlapparatus 400 or the random access power control apparatus 500 may beintegrated into the central processing unit 601. For example, thecentral processing unit 601 may be configured to carry out the randomaccess method described in Embodiment 1 or Embodiment 2.

For example, the central processing unit 601 may be configured to, byusing a pathloss estimated based on an synchronization signal/physicalbroadcast channel block (SS/PBCH block) and/or a channel stateinformation reference signal currently selected by UE, calculatetransmission power used by the UE in transmitting random accesspreambles. Or, the central processing unit 601 may be configured tocalculate the transmission power by using the first parameter.

Furthermore, reference may be made to Embodiment 1 and Embodiment 2 forother configuration manners of the central processing unit 601, whichshall not be described herein any further.

In another implementation, the random access power control apparatus 400or the random access power control apparatus 500 and the centralprocessing unit 601 may be configured separately. For example, therandom access power control apparatus 400 or the random access powercontrol apparatus 500 may be configured as a chip connected to thecentral processing unit 601, such as the random access unit shown inFIG. 6, with its functions being realized under control of the centralprocessing unit 601.

As shown in FIG. 6, the UE 600 may further include a communicationmodule 603, an input unit 604, a display 606, an audio processing unit605, an antenna 607 and a power supply 608, etc., functions of whichbeing similar to those in the related art, which shall not be describedherein any further. It should be noted that the UE 600 does notnecessarily include all the parts shown in FIG. 6, and furthermore, theUE 600 may include parts not shown in FIG. 6, and the related art may bereferred to.

It can be seen from the above embodiment that the UE may be adapted forrandom access procedures of the UE in such complex scenarios as multiplebeams.

Embodiment 6

FIGS. 7A and 7B are schematic diagrams of the communication system ofEmbodiment 6. As shown in FIG. 7A, the communication system 700 includesa network device 701 at a network side and UE 702. The UE 702, by usinga pathloss estimated based on an synchronization signal/physicalbroadcast channel block (SS/PBCH block) and/or a channel stateinformation reference signal (CSI-RS) currently selected by UE,calculates transmission power used by the UE in transmitting randomaccess preambles, or the UE calculates the transmission power by usingthe first parameter. The network device 701 at a network side receivesthe preambles transmitted by the UE 702. Furthermore, the network device701 at a network side may further configure any one or two or more ofthe above first to eighth thresholds used by the UE 702.

As shown in FIG. 7B, the communication system 700 includes multiplenetwork devices 701 at a network side and UE 702. The UE 702, by using apathloss estimated based on an synchronization signal/physical broadcastchannel block (SS/PBCH block) and/or a channel state informationreference signal (CSI-RS) currently selected by UE, calculatestransmission power used by the UE in transmitting random accesspreambles, or the UE calculates the transmission power by using thefirst parameter. The multiple network devices 701 at a network sidereceive the preambles transmitted by the UE 702. Furthermore, themultiple network devices 701 at a network side may further configure anyone or two or more of the above first to eighth thresholds used by theUE 702.

In an embodiment, a structure of the UE 702 is as described inEmbodiment 5, and a workflow of the system is as described inembodiments 1-4, the contents of which being incorporated herein, whichshall not be described herein any further.

It can be seen from the above embodiment that the system may be adaptedfor random access procedures of the UE in such complex scenarios asmultiple beams.

Embodiment 7

Embodiment 7 of this disclosure provides an information indicationmethod, applicable to a network side, such as a network device.

FIG. 8 is a flowchart of the information indication method of anembodiment. As shown in FIG. 8, the information indication method mayinclude:

block 801: first indication information used for indicating positionsand/or the number of time-frequency resources of a current cell fortransmitting an synchronization signal/physical broadcast channel block(SS/PBCH block) are/is transmitted, and/or second indication informationused for indicating positions and/or the number of time-frequencyresources of neighboring cells for transmitting synchronizationsignal/physical broadcast channel blocks (SS/PBCH blocks) are/istransmitted.

In an embodiment, the time-frequency resources used in transmitting theSS/PBCH block may be indicated by transmitting the first indicationinformation and/or the second indication information, which facilitatesUE in performing data transmission/reception and measurement.

In an embodiment, for different frequency ranges, an upper limit of thenumber of the time-frequency resources used for transmitting the SS/PBCHblock corresponding to a transmission period of a SS/PBCH block orsynchronization resource set (SS burst set), and positions of allpossible time-frequency resources used for transmitting SS/PBCH blocksat different upper limits of the number, may be predefined. For example:

frequencies less than 3 GHz, L=4;

frequencies between 3 GHz and 6 GHz, L=8; and

frequencies between 6 GHz and 52.6 GHz, L=64.

On the basis of the upper limit and positions of the number of thetime-frequency resources, the network device may configure the number oftime-frequency resources actually used for transmitting SS/PBCH blocksand a position of each time-frequency resource within a period of anSS/PBCH block.

In an embodiment, by transmitting the first indication informationand/or the second indication information, the network device mayindicate the time-frequency resources used in transmitting SS/PBCHblocks, which facilitates UE in performing data transmission/receptionand measurement.

In an embodiment, the first indication information and/or the secondindication information may be any one of the following:

1. Information indicating whether the predetermined positions in thetime-frequency resources are used for transmitting synchronizationsignals/physical broadcast channel blocks.

In an embodiment, the information indicating whether the predeterminedpositions in the time-frequency resources are used for transmittingsynchronization signals/physical broadcast channel blocks may be bits,and the predetermined positions may be, for example, positions oftime-frequency resources possibly used for transmitting SS/PBCH blockspreconfigured by the network device.

In an embodiment, the first indication information and/or the secondindication information may indicate based on bitmaps. For example, foreach predetermined position, whether a time-frequency resource at thisposition is used for actually transmitting SS/PBCH blocks may beindicated by one bit; for example, the bit being 1 indicates that thetime-frequency resource at this position is actually used fortransmitting SS/PBCH blocks, and the bit being 0 indicates that thetime-frequency resource at this position is not actually used fortransmitting SS/PBCH blocks.

2. Information indicating whether groups of the predetermined positionsin the time-frequency resources are used for transmittingsynchronization signals/physical broadcast channel blocks.

In an embodiment, the first indication information and/or the secondindication information may indicate based on bitmaps of the groups. Forexample, a predetermined number (such as 2) of predetermined positionsin a slot are divided into a group, and for each group, whether thereexist time-frequency resources actually used for transmitting SS/PBCHblocks in time-frequency resources in the group may be indicated by onebit; for example, the bit being 1 indicates that there exists at leastone time-frequency resource actually used for transmitting SS/PBCHblocks in the group, and the bit being 0 indicates that there exists notime-frequency resource actually used for transmitting SS/PBCH blocks inthe group. In an embodiment, when an upper limit of the number of thepredetermined positions is 4 (if the number of the predeterminedpositions in each group is 2), information of two bits may be used toindicate whether there exist time-frequency resources actually used fortransmitting SS/PBCH blocks in each group.

3. Index corresponding to a predetermined transmission pattern.

In an embodiment, a predetermined transmission pattern formed bytime-frequency resources used for transmitting SS/PBCH blocks may bepredefined, and a correspondence between the predetermined transmissionpattern and indices may be set. Hence, in a case where the firstindication information and/or the second indication informationcontain(s) indices, the UE may determine a transmission patternaccording to an index, thereby determining the number and/or positionsof the time-frequency resources actually used for transmitting SS/PBCHblocks.

In an embodiment, the predetermined transmission pattern may be, forexample, transmitting SS/PBCH blocks by using a former one possibleresource position in a slot only.

4. A last position in the time-frequency resources used for transmittingsynchronization signal/physical broadcast channel blocks and/or a totalnumber of positions in the time-frequency resources used fortransmitting synchronization signal/physical broadcast channel blocks.

For example, the first indication information and/or the secondindication information may include a total number of time-frequencyresources used for transmitting SS/PBCH blocks corresponding to atransmission period of SS/PBCH blocks, and/or a position of a lasttime-frequency resource. At this moment, SS/PBCH blocks are continuouslytransmitted starting from a first position of predeterminedtime-frequency resources by default, until the total number oftransmissions or the terminal of the time-frequency resources isreached.

5. A first position used for transmitting synchronizationsignal/physical broadcast channel blocks and a last position used fortransmitting synchronization signal/physical broadcast channel blocks inthe time-frequency resources and/or a total number of positions used fortransmitting synchronization signal/physical broadcast channel blocks inthe time-frequency resources.

For example, the first indication information and/or the secondindication information may include a first position of thetime-frequency resources used for transmitting SS/PBCH blockscorresponding to a transmission period of SS/PBCH blocks and a lastposition of the time-frequency resources used for transmitting SS/PBCHblocks and/or a total number of the time-frequency resources used fortransmitting SS/PBCH blocks.

In an embodiment, as shown in FIG. 8, the method may further include:

block 802: groups of the predetermined positions of the time-frequencyresources are configured.

Hence, the UE may receive the configuration information, and accordingto the first indication information and/or the second indicationinformation, determine a group in which resources are used fortransmitting SS/PBCH blocks.

In an embodiment, as shown in FIG. 8, the method may further include:

block 803: the correspondence between the predetermined transmissionpattern and indexes is configured.

Hence, the UE may receive the configuration information, and accordingto the first indication information and/or the second indicationinformation, determine a transmission pattern for transmitting SS/PBCHblocks.

In an embodiment, the network device may transmit the first indicationinformation via system information (SI) and/or radio resource control(RRC) signaling; wherein, the SI may include, for example, a physicalbroadcast channel (PBCH), and/or remaining minimum system information(RMSI), and/or other information.

In an embodiment, the network device may transmit the second indicationinformation via measurement configuration information, and/orredirection configuration information, and/or a handover command.

In an embodiment, the network device may configure the number oftime-frequency resources actually used for transmitting SS/PBCH blocksin the transmission period of SS/PBCH blocks and a position of eachtime-frequency resource, and generate the first indication informationaccording to a result of configuration.

In an embodiment, a network device of neighboring cells may transmitfirst indication information generated based on a result ofconfiguration of the network device of the neighboring cells, and when anetwork device of the current serving cell receives the first indicationinformation transmitted by the network device of the neighboring cells,it may process the first indication information, so as to generate thesecond indication information.

For example, in an embodiment, the network device of the current servingcell may, based on the first indication information transmitted by theneighboring cells, determine time-frequency resources of the neighboringcells actually used for transmitting SS/PBCH blocks, determine ameasurement window of the UE according to the determined time-frequencyresources, and generate the second indication information by using themeasurement window.

Hence, the second indication information may indicate onlyconfigurations of time-frequency resources of the neighboring cells usedfor transmitting SS/PBCH blocks within the measurement window; wherein,it is possible that the measurement window is unable to cover positionsof all possible time-frequency resources of the neighboring cells usedfor transmitting SS/PBCH blocks.

In an embodiment, based on the second indication information, the UE mayobtain the configurations of time-frequency resources of the neighboringcells used for transmitting

SS/PBCH blocks.

According to an embodiment, the UE may be facilitated in performing datatransmission/reception and measurement.

Embodiment 8

Embodiment 8 of this disclosure provides an information indicationmethod, applicable to a

UE side, such as UE.

FIG. 9 is a flowchart of the information indication method of anembodiment. As shown in FIG. 9, the information indication method mayinclude:

block 901: first indication information used for indicating positionsand/or the number of time-frequency resources of a current cell fortransmitting an synchronization signal/physical broadcast channel block(SS/PBCH block) are/is received, and/or second indication informationused for indicating positions and/or the number of time-frequencyresources of neighboring cells for transmitting synchronizationsignal/physical broadcast channel blocks (SS/PBCH blocks) are/isreceived.

In an embodiment, by receiving the first indication information and/orthe second indication information, the time-frequency resources used intransmitting SS/PBCH blocks may be indicated, which facilitates UE inperforming data transmission/reception and measurement.

In an embodiment, reference may be made to Embodiment 7 for explanationof the first indication information and/or the second indicationinformation.

In an embodiment, as shown in FIG. 9, the information indication methodmay further include:

block 902: configuration information on the groups of the predeterminedpositions is received.

Hence, the UE may receive the configuration information, and accordingto the first indication information and/or the second indicationinformation, determine a group in which resources are used fortransmitting SS/PBCH blocks.

In an embodiment, as shown in FIG. 9, the information indication methodmay further include:

block 903: configuration information on correspondence between thepredetermined transmission pattern and indexes is received.

Hence, the UE may receive the configuration information, and accordingto the first indication information and/or the second indicationinformation, determine a transmission pattern for transmitting SS/PBCHblocks.

In an embodiment, the UE may the first indication information via systeminformation (SI) and/or radio resource control (RRC) signaling.

In an embodiment, the UE may receive the second indication informationvia measurement configuration information, and/or redirectionconfiguration information, and/or a handover command.

According to this embodiment, the UE may be facilitated in performingdata transmission/reception and measurement.

Embodiment 9

Embodiment 8 of this disclosure provides an information indicationapparatus, configured in a transmitter end. This embodiment correspondsto the information method of Embodiment 9, with identical contents beingnot going to be described herein any further.

FIG. 10 is a schematic diagram of the information indication apparatusof the embodiment of this disclosure. As shown in FIG. 10, aninformation indication apparatus 1000 includes:

a first transmitting unit 1001 configured to transmit first indicationinformation used for indicating positions and/or the number oftime-frequency resources of a current cell for transmitting ansynchronization signal/physical broadcast channel block (SS/PBCH block),and/or second indication information used for indicating positionsand/or the number of time-frequency resources of neighboring cells fortransmitting synchronization signal/physical broadcast channel blocks(SS/PBCH blocks).

In an embodiment, the first transmitting unit 1001 may transmit thefirst indication information via system information (SI) and/or radioresource control (RRC) signaling.

In an embodiment, the first transmitting unit 1001 may transmit thesecond indication information via measurement configuration information,and/or redirection configuration information, and/or a handover command.

In an embodiment, reference may be made to Embodiment 7 for explanationof the first indication information and/or the second indicationinformation.

In an embodiment, as shown in FIG. 10, the information indicationapparatus 1000 may further include a first configuring unit 1002configured to configure groups of predetermined positions.

As shown in FIG. 10, the information indication apparatus 1000 mayfurther include a second configuring unit 1003 configured to configure acorrespondence between the predetermined transmission pattern andindexes.

In an embodiment, the apparatus 1000 may configure the number oftime-frequency resources actually used for transmitting SS/PBCH blocksin the transmission period of SS/PBCH blocks and a position of eachtime-frequency resource, and generate the first indication informationaccording to a result of configuration.

In an embodiment, a network device of neighboring cells may transmitfirst indication information generated based on a result ofconfiguration of the network device of the neighboring cells, and when anetwork device of a current serving cell receives the first indicationinformation transmitted by the network device of the neighboring cells,it may process the first indication information, so as to generate thesecond indication information. Hence, the apparatus 1000 of thisdisclosure may further include an indication information generatingportion (not shown), and reference may be made to Embodiment 7 for amethod for generating the second indication information by theindication information generating portion.

Based on the second indication information, the UE may obtainconfiguration of time-frequency resources of the neighboring cell usedfor transmitting SS/PBCH blocks.

According to this embodiment, the UE may be facilitated in performingdata transmission/reception and measurement.

Embodiment 10

The embodiment of this disclosure provides an information indicationapparatus, configured in a receiver end. This embodiment corresponds tothe information method of Embodiment 8, with identical contents beingnot going to be described herein any further.

FIG. 11 is a schematic diagram of the information indication apparatusof the embodiment of this disclosure. As shown in FIG. 11, aninformation indication apparatus 1100 includes:

a first receiving unit 1101 configured to receive first indicationinformation used for indicating positions and/or the number oftime-frequency resources of a current cell for transmitting ansynchronization signal/physical broadcast channel block (SS/PBCH block),and/or second indication information used for indicating positionsand/or the number of time-frequency resources of neighboring cells fortransmitting synchronization signal/physical broadcast channel blocks(SS/PBCH blocks).

In an embodiment, the first receiving unit 1101 may receive the firstindication information via system information (SI) and/or radio resourcecontrol (RRC) signaling.

In an embodiment, the first receiving unit 1101 may receive the secondindication information via measurement configuration information, and/orredirection configuration information, and/or a handover command.

In an embodiment, as shown in FIG. 11, the information indicationapparatus 1100 may further include a second receiving unit 1102configured to receive configuration information on groups ofpredetermined positions.

As shown in FIG. 11, the apparatus 1100 may further include a thirdreceiving unit 1103 configured to receive configuration information on acorrespondence between the predetermined transmission pattern andindexes.

According to an embodiment, the UE may be facilitated in performing datatransmission/reception and measurement.

Embodiment 11

The embodiment of this disclosure provides a communication system, withcontents identical to those in embodiments 7-10 being not going to bedescribed herein any further.

In an embodiment, the communication system may include:

a transmitter end configured with the information indication apparatus1000 described in Embodiment 9; and

a receiver end configured with the information indication apparatus 1100described in Embodiment 10.

FIG. 12 is a schematic diagram of the communication system of theembodiment of this disclosure, in which a case where the transmitter endis UE and the receiver end is a base station is shown. As shown in FIG.12, the communication system 1200 may include a base station 1201 and UE1202, the base station 1201 being configured with the informationindication apparatus 1000 described in Embodiment 9, and the UE 1202being configured with the information indication apparatus 1100described in Embodiment 10.

The embodiment of this disclosure further provides a receiver end, suchas a base station; however, this disclosure is not limited thereto, andit may also be other network devices. Following description shall begiven by taking a base station as an example.

FIG. 13 is a schematic diagram of a structure of the base station of theembodiment of this disclosure. As shown in FIG. 13, a base station 1300may include a central processing unit (CPU) 200 and a memory 210, thememory 210 being coupled to the central processing unit 200. Forexample, the memory 210 may store various data, and furthermore, it maystore a program for information processing, and execute the programunder control of the central processing unit 200.

In an embodiment, the central processing unit 200 may be configured tocarry out the functions of the information indication apparatus 1000.

For example, the central processing unit 200 may be configured toperform control, so that the base station carries out the informationindication method described in Embodiment 7.

Furthermore, as shown in FIG. 13, the base station 1300 may include atransceiver 220, and an antenna 230, etc. For example, functions of theabove components are similar to those in the related art, and shall notbe described herein any further. It should be noted that the basestation 1300 does not necessarily include all the parts shown in FIG.13, and furthermore, the base station 1300 may include parts not shownin FIG. 13, and the related art may be referred to.

The embodiment of this disclosure further provides a transmitter end,such as UE; however, this disclosure is not limited thereto, and it mayalso be other network devices. Following description shall be given bytaking UE as an example.

FIG. 14 is a schematic diagram of the UE of the embodiment of thisdisclosure. As shown in FIG. 14, UE 1400 may include a centralprocessing unit 100 and a memory 140, the memory 140 being coupled tothe central processing unit 100. It should be noted that this figure isillustrative only, and other types of structures may also be used, so asto supplement or replace this structure and achieve a telecommunicationsfunction or other functions.

In an embodiment, the central processing unit 100 may be configured tocarry out the functions of the information indication apparatus 1100.

For example, the central processing unit 100 may be configured toperform control, so that the UE carries out the information indicationmethod described in Embodiment 8.

As shown in FIG. 14, the UE 1400 may further include a communicationmodule 110, an input unit 120, a display 160 and a power supply 170. Itshould be noted that the UE 1400 does not necessarily include all theparts shown in FIG. 14, and furthermore, the UE 1400 may include partsnot shown in FIG. 14, and the related art may be referred to.

An embodiment of the present disclosure provides a computer readableprogram, which, when executed in a random access power control apparatusor UE, will cause the random access power control apparatus or UE tocarry out the random access power control method as described inembodiments 1 and 2.

An embodiment of the present disclosure provides a computer storagemedium, including a computer readable program, which will cause a randomaccess power control apparatus or UE to carry out the random accesspower control method as described in embodiments 1 and 2.

An embodiment of the present disclosure provides a computer readableprogram, which, when executed in an information indication apparatus ora network device, will cause the information apparatus or the networkdevice to carry out the information indication method as described inEmbodiment 7.

An embodiment of the present disclosure provides a computer storagemedium, including a computer readable program, which will cause aninformation indication apparatus or a network device to carry out theinformation indication method as described in Embodiment 7.

An embodiment of the present disclosure provides a computer readableprogram, which, when executed in an information indication apparatus orUE, will cause the information apparatus or the UE to carry out theinformation indication method as described in Embodiment 8.

An embodiment of the present disclosure provides a computer storagemedium, including a computer readable program, which will cause aninformation indication apparatus or UE to carry out the informationindication method as described in Embodiment 8.

The above apparatuses of the present disclosure may be implemented byhardware, or by hardware in combination with software. The presentdisclosure relates to such a computer-readable program that when theprogram is executed by a logic device, the logic device is enabled tocarry out the apparatus or components as described above, or to carryout the methods or blocks as described above. The present disclosurealso relates to a storage medium for storing the above program, such asa hard disk, a floppy disk, a CD, a DVD, and a flash memory, etc.

The method/apparatus described with reference to the embodiments of thisdisclosure may be directly embodied as hardware, software modulesexecuted by a processor, or a combination thereof. For example, one ormore functional block diagrams and/or one or more combinations of thefunctional block diagrams shown in FIGS. 4, 5, 10 and 11 may eithercorrespond to software modules of procedures of a computer program, orcorrespond to hardware modules. Such software modules may respectivelycorrespond to the blocks shown in FIGS. 1, 2, 3, 8 and 9. And thehardware module, for example, may be carried out by firming the softmodules by using a field programmable gate array (FPGA).

The soft modules may be located in an RAM, a flash memory, an ROM, anEPROM, and EEPROM, a register, a hard disc, a floppy disc, a CD-ROM, orany memory medium in other forms known in the art. A memory medium maybe coupled to a processor, so that the processor may be able to readinformation from the memory medium, and write information into thememory medium; or the memory medium may be a component of the processor.The processor and the memory medium may be located in an ASIC. The softmodules may be stored in a memory of a mobile terminal, and may also bestored in a memory card of a pluggable mobile terminal. For example, ifequipment (such as a mobile terminal) employs an MEGA-SIM card of arelatively large capacity or a flash memory device of a large capacity,the soft modules may be stored in the MEGA-SIM card or the flash memorydevice of a large capacity.

One or more functional blocks and/or one or more combinations of thefunctional blocks in FIGS. 4, 5, 10 and 11 may be realized as auniversal processor, a digital signal processor (DSP), anapplication-specific integrated circuit (ASIC), a field programmablegate array (FPGA) or other programmable logic devices, discrete gate ortransistor logic devices, discrete hardware component or any appropriatecombinations thereof carrying out the functions described in thisapplication. And the one or more functional block diagrams and/or one ormore combinations of the functional block diagrams in FIGS. 4, 5, 10 and11 may also be realized as a combination of computing equipment, such asa combination of a DSP and a microprocessor, multiple processors, one ormore microprocessors in communication combination with a DSP, or anyother such configuration.

This disclosure is described above with reference to particularembodiments. However, it should be understood by those skilled in theart that such a description is illustrative only, and not intended tolimit the protection scope of the present disclosure. Various variantsand modifications may be made by those skilled in the art according tothe principle of the present disclosure, and such variants andmodifications fall within the scope of the present disclosure. What isclaimed is:

1. A random access transmission apparatus, comprising: a controllerconfigured to: estimate a pathloss based on a selected synchronizationsignal/physical broadcast channel block (SS/PBCH block) or a selectedchannel state information reference signal (CSI-RS) and; determine thelower of a first transmission power and a second transmission power as atransmission power of a preamble via a physical random access channel(PRACH); and a transmitter configured to transmit the preamble via thePRACH at the determined transmission power; wherein, the firsttransmission power is according to a maximum transmission power, and thesecond transmission power is according to a preamble receiving targetpower and the estimated pathloss; and wherein, the preamble receivingtarget power is according to a power offset and a power ramping counter,and the power offset is determined based on a configuration parameter ofa subcarrier spacing for the preamble transmission.
 2. A random accesstransmission method, comprising: estimating a pathloss based on aselected synchronization signal/physical broadcast channel block(SS/PBCH block) or a selected channel state information reference signal(CSI-RS), determining the lower of a first transmission power and asecond transmission power as a transmission power of a preamble via aphysical random access channel (PRACH); and transmitting the preamblevia the PRACH at the determined transmission power; wherein, the firsttransmission power is according to a maximum transmission power, and thesecond transmission power is according to a preamble receiving targetpower and the estimated pathloss; and wherein, the preamble receivingtarget power is according to a power offset and a power ramping counter,and the power offset is determined based on a configuration parameter ofa subcarrier spacing for the preamble transmission.
 3. A communicationsystem, comprising: a terminal configured to: estimate a pathloss basedon a selected synchronization signal/physical broadcast channel block(SS/PBCH block) or a selected channel state information reference signal(CSI-RS); determining the lower of a first transmission power and asecond transmission power as a transmission power of a preamble via aphysical random access channel (PRACH); and transmit the preamble viathe PRACH at the determined transmission power; and a base stationconfigured to receive the preamble via the PRACH transmitted at thedetermined transmission power; wherein, the first transmission power isaccording to a maximum transmission power, and the second transmissionpower is according to a preamble receiving target power and theestimated pathloss; and wherein, the preamble receiving target power isaccording to a power offset and a power ramping counter, and the poweroffset is determined based on a configuration parameter of a subcarrierspacing for the preamble transmission.